A highly efficient asymmetric catalytic approach to synthesize -amino phosphonates by employing aldehydes, amines and diethyl phosphites under a chiral VANOL-derived zirconium complex was developed. The asymmetric induction of this direct three-component hydrophosphonylation reaction (Kabachnik-Fields reaction) of aliphatic aldehydes reaches over 90% ee for the first time. Broad scope of aromatic and aliphatic substrates bearing various functional groups including silyl ether, ester, amide, olefin, alkyne, azide etc. can be tolerated under the reaction conditions with good yield and ee. In the preliminary mechanism study, it was found that the 2-hydroxyl group on the aniline is crucial to the introduction of the enantioselectivity. Sphingoid bases are backbones of new class sphingolipids and they have four different members present in two-headed family with similar structure, but with different stereochemistry. The key step in the synthesis of sphingoid bases are nucleophilic addition between two heads and highly enantioselective trans- / cis-asymmetric aziridination, which is for setting four chiral centers in the structures.
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